Science

Hmm. You just had me thinking if that's true or not. I think money is an interesting thing. Inherently, it has no value, it's not rare, it's not useful. It is only useful because we as a society believe that it now has value. But that's more of a "we all decided that money is now worth something." Like.. a question of definition.

Another is safety. A society that believes they're safe will probably have a lot less tension and infighting than a society that believes they're unsafe.

On the other hand, you might erroneously believe that a bike helmet makes you much safer in traffic, to the point where you may ride more recklessly than otherwise and therefore be less safe than if you hadn't worn a helmet...